From patchwork Wed Jun 15 09:21:08 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suraj Jitindar Singh X-Patchwork-Id: 9177899 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C891D6021C for ; Wed, 15 Jun 2016 09:21:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B696A26490 for ; Wed, 15 Jun 2016 09:21:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AA7C927D5D; Wed, 15 Jun 2016 09:21:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 28BFD26490 for ; Wed, 15 Jun 2016 09:21:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753454AbcFOJVs (ORCPT ); Wed, 15 Jun 2016 05:21:48 -0400 Received: from mail-pa0-f68.google.com ([209.85.220.68]:33337 "EHLO mail-pa0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753330AbcFOJVn (ORCPT ); Wed, 15 Jun 2016 05:21:43 -0400 Received: by mail-pa0-f68.google.com with SMTP id ts6so1180108pac.0; Wed, 15 Jun 2016 02:21:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=oBzAiT0FBQZDCWVwEETy3DlmLazpx5xhhsNedI0tweM=; b=SAE333s2+nbiDo6fMCx2lQh5MVLrq/zjTzeTbPiqi41WW1gVm7uAZlua5QQZZJJMw4 dkPkWqYwDkIeFSsAYvdjw6f9PZGuxCmWFzmmchLT7D3k+YorIy2f2+/QPSCqlwmZBEk5 LKHY86hwRoBrFITfg/MHSQZSFFrmm5Tcr2zObfH0JFiJAxU6lCrR5nKhvy4rR0NeFOe9 opTpooJrzDiizVuBpz/bLfh9v8ye8b3N8p0Ke+3D0P6Euj4Dv+3ltzIBzTAxmaeJeCUV wOkdQD44lEg+d+j0E0Z2NF0lS4i7dux6lHNI2/fpiOLei7NonDewJHXgSYKa09I6P/y5 Sg1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=oBzAiT0FBQZDCWVwEETy3DlmLazpx5xhhsNedI0tweM=; b=Dper6N79u3sBCtoF1H2Hhh0q2fqUOICO4B75ftj66PQ9fXgEVQ5OFDAo6CuWbIxqHP hNoheoEFG5iUPu0LBntr1rQZV61kLepzlLPvcm3kvlEE+C4vivKtlSP3rOudXEgYZuEv y3HSvyjJNV7rzCw+zDuFcQZeN6S4sQUztO/N23r6bYvM9a/m0nQHSd1l11xsvPPedFJd xJkPpsgT9oAvpX8PgQaM7lomLpoJRV2VRbRKAAI7xy8+bRlRrxzP9GM4Zx9UN0H7bACY wcuqWGQMxJo1PpWU0TVOIbqMcpY1SIqM0IJtR7aZySsvWDnSY3M61kbMGoA7JlXSKkUU eYLw== X-Gm-Message-State: ALyK8tLLnXzpSzqwk4OSUnRHvqH+NYAe6Gsr8JGIL41km1ba7cg7pf909wkia2jbLDQpiA== X-Received: by 10.66.255.102 with SMTP id ap6mr2872208pad.2.1465982502154; Wed, 15 Jun 2016 02:21:42 -0700 (PDT) Received: from dyn253.ozlabs.ibm.com ([122.99.82.10]) by smtp.gmail.com with ESMTPSA id i5sm35423845pfk.14.2016.06.15.02.21.37 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 15 Jun 2016 02:21:41 -0700 (PDT) From: Suraj Jitindar Singh To: linuxppc-dev@lists.ozlabs.org Cc: kvm-ppc@vger.kernel.org, mpe@ellerman.id.au, paulus@samba.org, benh@kernel.crashing.org, kvm@vger.kernel.org, pbonzini@redhat.com, agraf@suse.com, rkrcmar@redhat.com, Suraj Jitindar Singh Subject: [PATCH 4/4] powerpc/kvm/stats: Implement existing and add new halt polling vcpu stats Date: Wed, 15 Jun 2016 19:21:08 +1000 Message-Id: <1465982468-18833-4-git-send-email-sjitindarsingh@gmail.com> X-Mailer: git-send-email 2.5.5 In-Reply-To: <1465982468-18833-1-git-send-email-sjitindarsingh@gmail.com> References: <1465982468-18833-1-git-send-email-sjitindarsingh@gmail.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP vcpu stats are used to collect information about a vcpu which can be viewed in the debugfs. For example halt_attempted_poll and halt_successful_poll are used to keep track of the number of times the vcpu attempts to and successfully polls. These stats are currently not used on powerpc. Implement incrementation of the halt_attempted_poll and halt_successful_poll vcpu stats for powerpc. Since these stats are summed over all the vcpus for all running guests it doesn't matter which vcpu they are attributed to, thus we choose the current runner vcpu of the vcore. Also add new vcpu stats: halt_poll_time and halt_wait_time to be used to accumulate the total time spend polling and waiting respectively, and halt_successful_wait to accumulate the number of times the vcpu waits. Given that halt_poll_time and halt_wait_time are expressed in nanoseconds it is necessary to represent these as 64-bit quantities, otherwise they would overflow after only about 4 seconds. Given that the total time spend either polling or waiting will be known and the number of times that each was done, it will be possible to determine the average poll and wait times. This will give the ability to tune the kvm module parameters based on the calculated average wait and poll times. Signed-off-by: Suraj Jitindar Singh --- arch/powerpc/include/asm/kvm_host.h | 3 +++ arch/powerpc/kvm/book3s.c | 3 +++ arch/powerpc/kvm/book3s_hv.c | 14 +++++++++++++- 3 files changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index b34efe8..2ece5fc 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -114,8 +114,11 @@ struct kvm_vcpu_stat { u32 emulated_inst_exits; u32 dec_exits; u32 ext_intr_exits; + u64 halt_poll_time; + u64 halt_wait_time; u32 halt_successful_poll; u32 halt_attempted_poll; + u32 halt_successful_wait; u32 halt_poll_invalid; u32 halt_wakeup; u32 dbell_exits; diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index ed9132b..6217bea 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -53,8 +53,11 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { "dec", VCPU_STAT(dec_exits) }, { "ext_intr", VCPU_STAT(ext_intr_exits) }, { "queue_intr", VCPU_STAT(queue_intr) }, + { "halt_poll_time_ns", VCPU_STAT_U64(halt_poll_time) }, + { "halt_wait_time_ns", VCPU_STAT_U64(halt_wait_time) }, { "halt_successful_poll", VCPU_STAT(halt_successful_poll), }, { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), }, + { "halt_successful_wait", VCPU_STAT(halt_successful_wait) }, { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid) }, { "halt_wakeup", VCPU_STAT(halt_wakeup) }, { "pf_storage", VCPU_STAT(pf_storage) }, diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 0d8ce14..a0dae63 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2688,6 +2688,7 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) cur = start = ktime_get(); if (vc->halt_poll_ns) { ktime_t stop = ktime_add_ns(start, vc->halt_poll_ns); + ++vc->runner->stat.halt_attempted_poll; vc->vcore_state = VCORE_POLLING; spin_unlock(&vc->lock); @@ -2703,8 +2704,10 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) spin_lock(&vc->lock); vc->vcore_state = VCORE_INACTIVE; - if (!do_sleep) + if (!do_sleep) { + ++vc->runner->stat.halt_successful_poll; goto out; + } } prepare_to_swait(&vc->wq, &wait, TASK_INTERRUPTIBLE); @@ -2712,6 +2715,9 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) if (kvmppc_vcore_check_block(vc)) { finish_swait(&vc->wq, &wait); do_sleep = 0; + /* If we polled, count this as a successful poll */ + if (vc->halt_poll_ns) + ++vc->runner->stat.halt_successful_poll; goto out; } @@ -2723,12 +2729,18 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) spin_lock(&vc->lock); vc->vcore_state = VCORE_INACTIVE; trace_kvmppc_vcore_blocked(vc, 1); + ++vc->runner->stat.halt_successful_wait; cur = ktime_get(); out: block_ns = ktime_to_ns(cur) - ktime_to_ns(start); + if (do_sleep) + vc->runner->stat.halt_wait_time += block_ns; + else if (vc->halt_poll_ns) + vc->runner->stat.halt_poll_time += block_ns; + if (halt_poll_max_ns) { if (block_ns <= vc->halt_poll_ns) ;